Air circulating apparatus



' the temperature of the air Patented Aug. 7, 1945- UNITED STATES PATENT orrlcs AIR CIRCULATING APPARATUS John R. Boyle, Chicago, 111., asslgnor to Westerlin and Campbell Company, Chicago, 111., a corporation of Illinois Application November 26, 1941, Serial No. 420,460 (Cl. 257-2) 22 Claims.

The present invention relates to air circulate ing'appar'atus adapted to be associated with an air circulating duct for the purpose of goveming the velocity, pressure, temperature, direction or flow, etc., of the air issuing from said duct. My improved apparatus can be utilized as a part of an air circulating system or air conditioning system arranged to discharge air or to circulate air in a rooml conditioning chamber, display case,

, or other enclosure.

The structure of the present invention takes the general form of an improved controllable grille or register which governs the volume, velocity, direction of'flow, etc.,of the issuing .air, and which also contemplates the use of improved thermal control means for governing the temperature of such issuing air.

One of the features of the invention is a unique construction and arrangement of plenum chamher which is incorporated in the apparatus at a point between the duct and the grille or other discharge opening. This plenum chamber reduces the velocity and changes the direction of flow of that portion of the air stream which, is being diverted from the main air stream flowing through the supply duct. This diverted air stream should not issue from the grille or discharge opening at too high a velocity, otherwise it will be objectionable from the standpoint of drafts. Furthermore, this divertedair stream should issue from the grille or discharge opening in a direction approximately at right; angles to the grille and to the length of the duct, othera conventional refrigerated display case for meats wise the distribution of the air will be uneven and the eflecti'veness of flow from theg-rille will be greatly reduced. The above arrangement of plenum tion of velocity and change of direction of flow. Another feature oi the invention resides in an chamber greatly improves the performance of the apparatus with regard to this reducimproved volumecontrol for governing the volume of thegair which is thus diverted from the main air stream of the duct for discharge out the air-supply duct, plenum chamber,

complish this thermal control by having the diverted air impinge against a thermal exchange conduit, and then varying the effective area of impingement of the air against said conduit.

Another feature of the invention resides in an improved arrangement-of deflecting vanes or fins associated with the discharge opening and capable of being readily positioned for directing the issuing air stream, at substantially any desired'angle with respect to the room or other enclosure.

' Another feature of the invention resides in the ability to manufacture and install the ap- 'paratus at relatively low cost, the construction being largely sheet metal and being preferably of unit lengths which can be readily joined together when a long continuous structure is desired.

Other features, objects and advantages of the inventionwill appear from the following detailed description of certain preferred embodiments thereof.

In the accompanying drawings illustrating these embodiments: l

Figure 1 is a horizontal sectional view through and the like, showing a one embodiment of my invention arranged for cooling the circulated air; Figure 2 is a transverse sectional view through cooling coil and grille or discharge opening;

Figure 3 is a sectional view similar to Figure 2 but showing a modified construction wherein the volume control is responsive to static pressure;

Figure 4 is a fragmentary sectional view, similar'to Figures 2 and 3, showinga modified construction wherein the volume control is responsive to manual adjustment;

' Figure 5 is a sectional view similar to Figure 4,

showing a modified construction wherein the volume control is responsive to temperature, static pressure and manual adjustment;

throughthe grille or discharge opening into the room. This volume control may be arranged to respond to temperature, static pressure, or manual regulation in different preferred embodiments which I shall hereinafter describe.

Another feature of the invention resides in an improved thermal control means'for governing issuing from the discharge opening or grille. This thermal control may be'for the purpose of. heating the air or cooling the air, depending upon the requirements of the particular installation. I preferably ac- 7 are vertical sectional views of 9 are vertical sectional views of I sectional view taken j or windows, not shown, for displaying the meats or other commodities contained within the case. The air circulating system comprises the long air supply duct 25 which extends substantially throughout the ntire length of the display case along the bottom surface of the display space. A blower 26, driven by an electric motor 21, is positioned at one end of the case and has its outlet 26' connected to discharge into the end 01' the duct 25. The duct is of conventional sheet metal construction comprising the top wall-28, side wall 29, and bottom wall 3|. The bottom wall 3| is curved upwardly at the other side of the duct structure to form a grille casing or outlet casing, as indicated at 32, which casing is continued upwardly and backwardly as indicated at 33 to form the grille slot or discharge opening 34, This discharge outlet 34 extends substantially the entire length of the duct 25, and located at spaced points along its length are outlet deflector vanes 35. These have a tight frictional mounting on supporting pins or bolts 36 which xtend down through the outlet wall 33 and top wall 28 of the duct. The deflector vanes 35 can be manually turned to different deflecting angles for securing the desired distribution of air to different points in the display case. A return air space 38 is defined between the vertical side wall 29 of the air supply duct and the adjacent vertical wall 22 of the case, through which air space or channel the return air is recirculated back to the blower 26.

In the embodiment illustrated in Figure 2, the

connects the first plenum chamber 4| with the second plenum chamber 42., The two vanes are link connected at 64 and are arranged to be swung air conveyed through th supply duct 25 is required to pass through a flrst'plenum chamber 4| and through a second plenum chamber 42 before issuing from the discharge outlet 34. One' or more lengths of heat exchange conduit 44 extend longitudinally of the second plenum chamber 42. In the present situation wherein the air is to be cooled, these thermal transfer conduits 44 will carry a suitable refrigerant or other cooling medium.

A high velocity throat 41 governs the volume of air entering th first plenum chamber 4| from the supply duct 25. This high velocity throat is made controllable in area in response to temperature, static pressure, or manual adjustment. In the embodiment illustrated in Figure 2, the area of this throat or inlet varies in response to temperature. The two plenum chambers 4| and 42 are separated from the main area of the duct by a movable wall 48 and a stationary wall 49. The movable wall 46 'can be flexed upwardly and downwardly for varying the respective area of the high velocity throat 41. The free end of this flexible wall 48 carries a pivot lug,5| which is pivotally connected by way of link 52 with one arm of a bell crank lever 53. Th lever has fulcrum mountin at 64 on a suitable bracket or other stationary point of support projecting from the duct wall 29. Pivotally connected with the arm of the bell crank lever53 is a link 56 which extends to .a thermally responsive element preferably consisting of a thermal bellows 51. ThlS bellows is shown as being mounted in a suitable bracket 58 disposed on the outer side of the duct wall 29, where it will be exposed to the flow of return air passing through the return air space 38 back to the inlet of the blower 26. The operating'connection between the thermal bellows 51 and the flexible wall 48 is preferably such that when the temperature of the return air rises to a substantially predetermined point or range, the expansion of the bellows 51 becomes operative to open the high velocitythroat 41 to a greater degree, for permitting a larger volume of air to flow upwardly or downwardly through an operating lever 65 connected by a rod 66 with a control unit 61. The control unit is shown as a thermally responsive bellows, similar to the bellows 51, said latter bellows '61 being also mounted on the bracket 58 disposed within the return air duct 38. When the temperature in this return air duct rises to a predetermined point or range, the expansion of the bellows 61 swings the deflecting vanes 6| and 62 downwardly so as to cause the air issuing through the throat 63 to have a greater area of impingement on the heat'exchange pipe 44. Assuming this pipe to be conveying a coolant, this greater area of impingement -wil1 subject the air to a greater cooling influence for lowering the temperature within the display case. Conversely, when the temperature of the return air falls to a predetermined point or range, the contraction of the bellows 61 swings the deflecting vanes 6| and 62 in an u ward direction, toward or into the dotted line positions, for re ucing the area of impingement of theair against the conduit 44, or for avoiding any impingement of the air against said conduit, thereby reducing or avoiding the heat'transfer action between the air and the conduit. The two thermal bellows 51 and 61 can be adjusted and arranged to handle diilerent ends of the entire range of temperature control, such, for example, as by having the bellows 51 handle the low end of the range and having the bellows' 61 handle the high end of the range. As an alternative embodiment, both thermal bellows could be adjusted and arranged to actconjointly over substantially the same portion of th control range.- 'The throat 41 .and its movable wall- 48 preferably extend through a major portion of the length of the duct 25, and, similarly, the second throat 63 and deflecting baflles 6|, 62 preferably throat 41 responds to the static pressure in the duct 25. In this embodiment, a light compression spring 1|, or a plurality of such springs disposed at spaced points along the length of the duct, tend .to flex the movable wall- 48 upwardly to increase the size of the throat 41. This action of the springs is'opposed by the static pressure of the air traveling through the duct 25, the greater the static pressure themore the throat is restricted so that the air passing into the plenum chamber 4| is maintained at a fixed volume or rate, or is held within predetermined limits of volume or rate. The spring 1| surrounds a stem or guide 12 which passes up through the bottom wall 3| and through the end flange 48' of the movable wall 48. A limiting stop or head 13 on the upper end of said stem limits the upward flexing movement of'the wall. The stem 12 maybe adjustable, if desired, as by threading thelower by'the outer end of the bellows 51.

. bottom wall 3|. By screwing the stem upwardly or downwardly within this tapped guide boss the head 13 can be adjusted for a greater or lesser range of movement of the movable wall 48. Adjusting means may also be-provided for adjusting the pressure of the spring H, if desired.

This modified embodiment of. Figure 3 controls the volume of air issuing from the duct by controlling the size of the high velocity throat 41, and controls the temperature of the issuing air by controlling the deflecting vanes 6| and B2 in substantially the manner previously described in connection with Figure 2. This modified embodiment illustrates the use of a motion multiplying lever 15 and link T6 for increasing the range of movement of the vane actuating lever 65, which motion multiplying mechanism may be embodied in the construction of Figure 2 if desired.

In the modified constructionshown in Figure 4, the high velocity throat 4! is arranged for manual adjustment. In this construction, an ad justing screw 8| has rotatable, non-shiftable mounting in a guide boss 82 carried by. the bottom Wall 3|. The upper threaded end of this screw passes through the end flange 48' of the movable wall 48 and has threaded engagement with a nut hub or bracket 83 which is secured to said flange 48. Rotation of the head 85 at the lower end of the screw 8| is operative to flex the movable wall 48 upwardly or downwardly for varying theeflective area of the throat 41; This modified embodiment can have the same temperature control exercised at the other high velocity throat B3 operative through the medium of the deflecting vanes 6| and 62 to control the area of impingement of the air stream against the heat exchange co'nduit 44. These deflecting vanes 6| and 62 are arranged to respond to the thermal bellows 61 in the same manner previously described.

In the modified construction illustrated in Figure 5, the flow through the high velocity throat 41 is responsive to temperature, static pressure. and manual adjustment. The static pressure re sponse is similar to that described above in connection with Figure 3, comprising a compression spring ll confined between the end flange 48 of the movable wall 48 and the stationary bottom wall 3|, The stem 1| extending through said spring carriesthe upper end stop 13 for limiting the upward movement of the wall 48., and also carries a lower stop shoulder or collar 81 for limiting the downward movement of the wall 48. Also mounted in the throat 41, preferably anterior of the spring and rod assembly ll, 12, is a balanced damper valve 9| mounted on a horizontal central pivot 92. A pivot lug 93 on the anterior face of this valve has pivotal connection through link 94 with a swivel head 95 mounted on the inner end of the adjustable rod 96. This rod or stem 96 extends outwardly through a thermal bellows 51". The outer end of said stem carries an adjusting head 9'! for rotating the stem, this outer portion being threaded at 98 for screwing inwardly and outwardly of a nut 99 carried The bellows may comprise. an innner expansible portion through which the rod 96 passes, or a tight fitting joint may be. established between the rod and each end of the bellows. It will be evident that rise and fall of temperature in the air stream acting on the bellows will expand. or contract the bellows for oscillatingthe damper 9| toward open or closed positions. A manual adjustment may be superposed on this automatic temperature control by rotating the adjusting knob 91 so as to thread the stem 96 inwardly or outwardly with respect to the bellows, the inner end of the stem rotating within the swivel head 95. Such manual adjustment shifts the position of the damper valve 9| withrespect to the temperature range of movement effected by the bellows. The second high velocity throat 63 with its associated deflector vanes GI and 62 responds to the other bellows B1 in the same manner previously described.

Figures 6, 7, 8, 9, and 10 illustrate modified constructions wherein the grille and associated apparatus are disposed substantially vertically. These embodiments are particularly adaptable to rooms and other like enclosures wherein the air supply duct is mounted on or recessed into the side wall of the room adjacent to the ceiling. In each of these embodiments, the air supply duct is indicated at I14, and preferably consists of a sheet metal conduit of rectangular cross-section. This conduit is shown as being set back into a recess in the wall H16, but it will be understood that the duct might be disposed externally of the wall. My improved grille structure is preferably made in unit lengths, each of which can be'mounted as a single unit, or which can be mounted end to end along a relatively long wall. Such portion of the air duct I04 as is intended to receive one or more of these units of grille structure has its front side left open to receive such unit or units. Each grille section comprises a sheet metal shell or casing I08 having top and bottom mounting flanges MM and |D8b for securing the casing to the duct- I04, such as by sliding these flanges endwise into interlocking engagement with cooperating flanges Ma and I041) on the duct, as shown in Figure 6. Said casing also comprises a top wall 18c, an inclined front wall IUBd, a vertical front wall lite, and a bottom wall I081. The grille slot or opening for discharging the air into the room is indicated at I, the top and bottom margins of this opening being defined by the upper and lower sheet metal flanges or lips H2 and H3. In the installation of the grille structure, these flanges can be bent to deflect the issuing air stream to different vertical angles, and can be shaped or bent to govern the velocity of the issuing air stream. Figure 6 illustrates the flanges extending horizontally for producing a normal horizontal flow. Figure 7 illustrates the flanges bent upwardly for producing an upwardly deflected blast. Figure 8 illustrates the flanges bent downwardly for securing a downwardly deflected blast. Figure 9 illustrates the flanges bent toward each other for producing a high velocity discharge of the air, and it will also be understood that said flanges can be bent outwardly away from each other to produce a low velocity discharge. It will be understood that any one of the embodiments illustrated in Figures 6, 7, 8, and 9 can have its flanges H2, H3 adjusted to any one of the relations illustrated in the other figures.

Fixedly mounted at horizontally spaced distances along the length of the grille casing are vertically extending vanes I I5, these preferably being composed of sheet metal, and being spot welded, soldered, or otherwise secured in the grille casing. 'The main body of each vane 5 extends substantially at right angles to the length of the grille-unit, but projecting forwardly from each vane, within the discharge opening HI, is

a deflection tab or flange II6 which can be bent laterally to right or left along the line indicated by the dotted line II1. By bending these deflection tabs H6 in one direction or the other, any portion of the issuing air stream can be deflected to right or left. In some situations, a portion of the air stream may be deflected in one direction and another portion in the other direction for producing a desired circulation. The horizontal component imparted to the air stream by the bendable tabs [I6 can be combined with any desired vertical component or with any desired velocity change effected by bending the flanges H2, H3.

The embodiments illustrated in Figures 6 and '7 each comprise a first plenum chamber I2I and a second plenum chamber I22 arranged in series relation between the air supply duct. I04 and the grille opening III. An inner wall I26 extends downwardly from the top wall I08c and defines the dividing partition between the supply duct I04 and the second plenum chamber I22. A flexible wall I28 extends downwardly from the lower portion of the upper wall I26, and serves to par-- tition the first plenum chamber I2I from the air supply duct I04. A flange I23 projecting angularly from the lower portion of the flexible Wall I28 constitutes the controllable portion of a high velocity throat I29 through which the air is conveyed from the supply duct I04 into the lower portion of the first plenum chamber I2I. This high velocity throat is made controllable in area in response to temperature, static pressure, manual adjustment, or other control condition. In the embodiment illustrated in Figure 6, the area of this throat or inlet varies in response to temperature. The flexing of the wall I28 to left and right causes the flange I28 to move toward and away from a ridge or crown I3I formed in the bottom wall 108 thereby varying the effective area of the entrance throat I29. An actuating rod I32 has swiveled connection with the flexible wall I28 and extends outwardly of the casing through the front wall I086. Here this rod has operative connection with a thermally responsive bellows I33, which is suitably mounted on the front wall I08e, as in a mounting bracket I34. When the temperature within the room or other enclosure rises to a substantially predetermined point or range, the expansion of the bellows I33 becomes operative to open the high velocity throat I29 to a greater degree, for permitting a larger volume of air to flow from the duct I04 through the plenum chambers I2I and I22 and out through the grille opening I II into the room. If it is desired to superpose a manual adjustment upon the automatic. control exercised by the bellows I33, such can be readily accomplished by arranging the actuating rod I32 for a manual threaded adjustment inwardly and outwardly with respect to the bellows I33. For example, the intermediate portion of the rod I32 may be threaded for screwing inwardly and outwardly of a nut I33 carried by the inner end of the bellows I33. The outer portion of the rod extends through the bellows, such as through an inner expansible portion thereof, and carries a knob E31 at its outer end, by which the rod may be rotated for screwing the rod inwardly or outwardly within the nut I36, and thereby adjusting the effective area of the throat I29. If the air circulating apparatus is intended to heat a conditioning enclosure, the expansion of the bellows I34 may be arranged to restrict the throat'l 29. For'example, the bellows I33 might be reversed to have its inner end stationarily mounted in the bracket I34 and to have its outer end movable and carrying the nut I36.

The volume of air impinging against the thermal exchange conduit 44a in the second and I42 are adapted to vary the volume of the i air which is caused to impinge against the thermal transfer conduit 44a in the upper plenum chamber I22. In installations where the air cir-- culating apparatus performs a cooling function, the conduit 44a will carry a suitable refrigerant or other cooling medium, and upon a predetermined rise of temperature within the room or other enclosure the bellows I41 will expand to swing the deflecting vanes I4I, I42 into upright positions for causing a greater proportion of the air to impinge against the thermal transfer conduit. Upon a predetermined lowering of the temperature within the room, the contraction of the bellows I41 will swing the vanes I4I, I42 to the left for reducing the proportion of the air which is caused to impinge against the conduit 44a. In the converse type of installation wherein the air circulating apparatus is to maintain a relatively high temperature within a conditionin chamber or the like, the operating relation would be reversed, as b reversing the bellows I41 in the manner described above in connection'with the bellows I33. In such arrangement, if there were an undesirable drop of temperature, the action of the bellows I41 would be to cause more air to impinge directly against the thermal transfer conduit Me, which would then be carrying a heating medium.

In the cooling type of installation, there may be a substantial amount of condensate which will precipitate from the side walls of the plenum chambers I2I and I22 and from the relatively cold conduit44a. In such type of installation, the ridge I3I extending lengthwise of the bottom wall I081 prevents collected moisture from flow ing out of the plenum chamber I2I into the air supply duct I04. A drainage trough I5I may be extended along the under side of the bottom wall I08f, and be placed in communication with the bottom of the lower plenum chamber I2I through longitudinally spaced apertures, this drainage trough leading to any suitable drain outlet.

Figure '7 illustrates a modified construction which is substantially identical with that illustrated in Figure 6, except that the first high velocity throat I29 is made responsive to static pressure and to manual adjustment, rather than to temperature and manual adjustment. In this modified construction, the actuating rod I32 extends outwardly of the casing I08 and carries a flanged thrusting head I54 at its outer end. A compression spring I55 has one end centered on this thrusting head, and has its other end centered on an adjustable head I56. The latter head is mounted on a threaded stem I51 which screws through a tapped hub carried by a supporting bracket I59, the outer end of said stem carrying 2,380,935 a knob I61, by which the adjustable head use may be shifted inwardly or outwardly to vary the pressure of the spring 1 55. A sufficient range of adjustment can be given the head I56 and knob l6! to produce the effect of superposing a manual control upon the static pressure control to which the flexible wall I28 is adapted to respond. The greater the static pressure within the supply duct I04, the more the throat 129 is restricted, so that the air passing into the plenum chambers l2! and I22 is maintained at a fixed volume or rate, or is held within predetermined limits of volume or rate.

Figures 8 and 9 illustrate other modified constructions in which only a single plenum chamher I Zla is interposed between the air supply duct I04 and the grille outlet III. In both of these embodiments, the dividing wall I230; is made flexible so as to be capable of varying the effective area of the high velocity throat l29a leading from the supply duct into the plenum chamber. In constructions adapted to effect a thermal exchange between the air and conduit means contained within the grille structure, a single thermal exchange conduit 4411 may be disposed within the plenum chamber lZla, substantially as disclosed in Figures 6 and '7, or a plurality of smaller conduits 44b, 44c and 44d may be substituted for the relatively large conduit, and be located within the plenum chamber at points securing the most desirable or effective impingement of the air on said conduits.

The embodiment shown in Figure 8 is arranged to be temperature responsive, and, in addition, has a manual adjustment superposed thereon. This arrangement is similar to that employed for flexing the wall I28 of Figure 6, comprising an actuating rod 132a extending out through the front wall of the casing and responding to the expansion and contraction of a thermally responsive bellows l33a mounted in a bracket Ma. The intermediate portion of the rod [32a may be threaded for screwing inwardly and outwardly of a nut l36a carried by the inner end of the bellows l33a, and the outer portion of the rod may be provided with a knob 13141, by which the rod may be rotated for screwing inwardly and outwardly within the nut mm. This serves to adlust the effective area of the throat 129a, constituting a manual adjustment superposed upon the automatic temperature adjustment which is brought about by the bellows l33a.

The embodiment illustrated in Figure 9 is similar to that illustrated in Figure '7, to the extent that the flexible wall I28a is arranged to respond to an automatic,.,static pressure control, and is also arranged to respond to a manually actuated control superposed upon the automatic static pressure control. The actuating rod 532a extends outwardly through the casing [08 and carries a flanged thrusting head .l54a at its outer end. A compression spring I55a acts between this thrustinghead and an adjustable outer head 156a. The outer head 156a is carried on a threaded. stem l51a which screws through a tapped boss carried by the bracket [5942. Rotation of the outer adjusting knob 1 Blu is operative to shift the head I 56a inwardly and outwardly to adjust the pressure of the spring l55a. A substantial range of adjustment afforded through the threaded stem [51a and knob lfila enables a manual adjustment to be superposed upon the spring l55a, adequate to effect any ordinary range of manual adjustment that might be desired. It

will be understood that the spring 155a also responds automatically to the static pressures prevailing against the flexible wall 128a, for obtaining the automatic static pressure control referred to above in connection with the preceding embodiment.

While I have illustrated and described what I regard to be the preferred embodiments of my invention, nevertheless it will be understood that such are merely exemplary and that numerous modifications and rearrangements may be made therein without departing from the essence of the invention. In embodiment in which there is to be no heating or cooling of the air within the grille section, the thermal exchange conduits 44, Ma, 44b, M0, and 44d may be dispensed with.

I claim:

1. In air circulating apparatus, the combination with an air supply duct for supplying air under pressure, of a grille casing extending substantially longitudinally of said air supply duct and adapted to receive air therefrom, a grille slot in said casing through which air is discharged into the room or other enclosure, a thermal exchange conduit in said grille casing, and means responsive to the pressure in said air supply duct for automatically controlling the flow of air through said grille casing.

2. In air circulating apparatus of the class described, the combination of an air supply duct, a grille casing extending substantially longitudinally of said supply duct, a high velocity inlet throat for permitting air to enter said grille casing from said supply duct, a grille slot for permitting air to discharge from said grille casing tothe room or other enclosure, a deflecting flange extending substantially horizontally along said grille slot and adapted to be positioned to deflect air issuing from said grille slot in an upward or downward direction, and means for varying the size of said high velocity throat in inverse relation to the static pressure in said air supply duct to control the volume of air passing through said grille casing.

3. In air circulating apparatus of the class described, the combination of a substantially horizontal air supply duct recessed into the wall of a room near the ceiling, a grille casing extending substantially longitudinally of said supply duct and overlying said air supply duct on the room side, a plenum chamber defined between said grille casing and said air velocity duct, a high velocity inlet throat extending longitudinally of said supply duct and grille casing for permitting airto enter said plenum chamber from said supply duct, said inlet throat comprising a movable wall adapted to be shifted to vary the size of said thoat, a grille slot for permitting air to discharge from said plenum chamber to the room, deflecting flanges extending along the top and bottom edges of said grille slot and adapted to be bent upwardly or downwardly for varying the effective size of said grille slot or for deflecting in an upward or downward direction the air issuing from said grille slot, said plenum chamber being of said air supply duct and said grille casing, a partition separating said plenum chamber from said supply duct comprising a movable wall, said movable wall defining one side of a high velocity inlet throat through which air passes from said supply duct to said plenum chamber, a grille slot in said grille casing for permitting air to discharge from said plenum chamber to the room, said plenum chamber being of suflicient volume to effect a marked reduction of velocity of the air entering said chamber through said throat, and temperature responsive means for automatically shifting the movable wall to vary the size of said throat.

5. In air circulating apparatus of the class described, the combination of an air supply duct, a grille casing extending substantially longitudinally of said supply duct, a plenum chamber in said grille casing, a partition separating said plenum chamber from said supply duct comprising a movable wall, said movable wall defining one side of a high velocity inlet throat through which air passes from said supply duct to said plenum chamber, a grille slot in said grille casing for permitting air to discharge from said plenum chamber to the room or other enclosure, said plenum chamber being of suflicient volume to effect a marked reduction of velocity of the air entering said chamber through said throat, and spring means coacting with said movable Wall for causing said wall to shift and vary the size of said inlet throat automatically in response to the static pressure in said supply duct.

6. In air circulating apparatus for a room or like enclosure, the combination of a substantially horizontal air supply duct mounted on a wall of said room near the ceiling, a grille casing extending substantially longitudinally along the room side of said supply duct and adapted to receive air therefrom, means for controlling the flow of air from said duct to said casing, a grille slot in said casing through which air is discharged, and deflecting means associated with said grilleslot and adapted to be set to deflect the air laterally at a predetermined angle or angles relatively to the length of said slot.

'7. In air circulating apparatus for a room or the like, the combination of a substantially horizontal air supply duct recessed into a wall of said room near the ceiling, a grille casing extending substantially longitudinally with respect to said supply duct and detachably secured thereto, said grille casing adapted to receive air from said duct, means for controlling the flow of air from said duct to said casing, a grille slot in said casing through which air is discharged, and deflecting flanges extending along the top and bottom edges of said grille slot and adapted to be bent upwardly or downwardly for deflecting the air upwardly or downwardly or for controlling the velocity of flow through said slot.

8. In air circulating apparatus for a room or the like, the combination of an air supply duct recessed into a wall of said room near the ceiling. a grille casing extending along the length of a considerable portion of said air supply duct on the room side thereof and receiving air therefrom, cooperating interlocking flanges on said duct and said casing for detachably securing the two together, a plenum chamber defined in said casing, a restricted inlet through which the air passes from said supply duct to said plenum chamber, means for controlling the flow of air through said restricted inlet, a discharge slot in said grille casing through which the air is discharged into the room or other enclosure, fins disposed in said plenum chamber and extending across said grille slot substantially at right angles thereto, deflecting tabs carried by said fins and projecting outwardly of said slot, said tabs adapted to be bent laterally for deflecting the issuing air horizontally with respect to the length of said slot, and deflecting flanges extending along the top and bottom edges of said grille slot and adapted to be bent upwardly or downwardly for deflecting the issuing air vertically with respect to the length of said slot.

9. In apparatus of the class described, the combination of an air supply duct, a register casing extending lengthwise of said duct, cooperating locking flanges on said supply duct and on said register casing adapted to be slid endwise into interlocking engagement with each other, a plenum chamber in said register casing, a flexible wall separating said plenum chamber from said supply duct, the lower edge of said flexible wall defining one edge of a restricted throat extending longitudinally of said supply duct and register casing and establishing communication between the lower portions thereof, means for shifting said flexible wall to adjust the effective area of said throat, an outlet slot extending lengthwise of said register casing adjacent the upper portion thereof, and deflecting means associated with said outlet slot for deflecting the air issuing therefrom.

10. In air circulating apparatus including a substantially horizontal air supply duct recessed into the wall of a room near the ceiling, the combination therewith of a grille section detachably secured to said duct on the room side thereof and adapted to receive air from said duct, governing means acting on the flow of air passing through said grille section, temperature responsive means for automatically actuating said governing means, and means for superposing a manual control upon the automatic control exercised by said temperature responsive means.

11. In air circulating apparatus including an air supply duct, the combination therewith of a grille section adapted to receive air from said duct, governing means acting on the flow of air passing through said grille section, means responsive to the static pressure in said air supply duct for automatically actuating said governing means, and means for superposing a manual control upon the automatic control exercised by said pressure responsive means.

12. In fluid circulating apparatus, the combination of a fluid supply duct having an aperture in one wall thereof, a grille section fitting over said aperture, cooperating locking flanges on said supply duct and on said grille section adapted to be slid endwise into interlocking engagement with each other, said grille section comprising a plenum chamber, an inlet opening leading from said supply duct to said plenum chamber, an outlet opening leading from said plenum chamber, means coacting with said inlet opening for controlling the fluid flow from said supply duct to said plenum chamber and means coacting with said outlet opening for controlling the fluid flow issuing from said plenum chamber.

13. In air circulating apparatus for installation directly in a room to be air conditioned, the combination of an air duct extending along one wall of the room for supplying air under pressure, a grille structure separable from said duct extending longitudinally of said air duct on the room side of said duct, cooperating interlocking flanges on said duct and on said grille structure adapted to be slid endwise into interlocking engagement with each other, said grille structure having a discharge opening through which air is discharged into the room, a plenum chamber interposed between said duct and said discharge opening, a regulatable volumeeontrol device for governing the volume of air issuing from said duct into said plenum chamber, and thermal control means for governing the temperature of the air issuing from said discharge opening, said thermal control means comprising a thermal exchange conduit disposed between said volume controlled device and said discharge opening and against which the 'air under pressure from said duct is adapted to impinge in its flow from said duct to said-discharge opening.

14, Inair circulatingapparatus for a room or the like, the combination of an air supply duct extending substantially horizontally of the room structure defining a plenum chamber therein extending along the length of said duct and grille structure, a flexible wall separating said plenum chamber from said duct, a high velocity inlet throat defined along the lower edge of said flexible wall for admitting air under pressure from said air duct into the lower portion of said plenum chamber, means for shifting said flexible wall to adjust the effective area of said throat whereby to control the volume of air entering the lower portion of said plenum chamber from said air duct, a horizontal grille slot formed in the room side of said grille structure discharging from the upper portion of said plenum chamber and extending throughout the major portion of the length of said grille structure, and deflecting flanges extending along the top and bottom edges of said grille slot and adapted to be bent upwardly or downwardly for varying the effective size of said grille slot or for deflecting in an upward or downward direction the air issuing from said grille slot, said grille structure producing a velocity of air flow into the room substantially at right angles to the direction of air flow through said air supply duct.

15. In air circulating apparatus of the class described, the combination of an air duct for supplying air under pressure, a grille or discharge opening through which said air is discharged into the room or other enclosure, a plenum chamber interposed between said ductand said grille for passing substantially all of the air flowing from said duct to said grille, said plenum chamber .re ducing the velocity and changing the direction of flow of the air diverted from said duct, volume control means for governing the volume of substantially all of the air flowing from said duct to.

said grille, means responsive to the static pressure in said air duct for regulating said volume control means, thermal control means for governing the temperature of the air issuing from said grille, said thermal control means comprising a thermal exchange conduit against which the air is adapted to discharge in its flow from said duct to said grille, and temperature responsive means for regulating the effective area of impingement of the air against said thermal exchange conduit.

16. In air circulating apparatus for a room or the like, the combination of a relatively long grille casing extending substantially horizontally in said room adjacent the ceiling thereof and Lil Lin

lower edge movable for volume adjustment, and -means for moving the lower edge of said volume damper to control the volume of air transferred from said air supply duct to said grille casing.

17. In air circulating apparatus for a room or the like, the combination of a relatively long grille casing extending substantially horizontally in said room adjacent the ceiling thereof and having a relatively long substantially horizontal grille slot therein for discharging air into said room near the ceiling in the form of a thin sheet of .air distributed over a relatively wide area of f the room, an air supply duct extending lengthwise along said grille casing for communication therewith along the major portion of the length of said grille casing, a relatively long damper disposed between said supplyduct and said grille casing having a movable lower edge, means cooperating with said movable lower edge to define a relatively long horizontally extending inlet throat between said supply duct and said grille casing, said inlet throat being disposed adjacent the lower portion of said grille casing and said grille slot being disposed adjacent the upper portion of said grille casing, whereby a plenum chamber is defined in said grille casing between said inlet throat and said grille slot to change the velocity head of the air to a pressure head, and means for adjusting said damper.

18. In air circulating apparatus for a room or the like, the combination of a relatively long grille casing extending substantially horizontally in said room adjacent to the ceiling thereof and having discharge means for discharging air into said room near the ceiling in the form of a thin sheet of air distributed over a relatively wide area of the room, an air supply duct extending lengthwise along said grille casing for communication therewith along the major portion of the length of said grille casing, a relatively long controllable volume damper disposed between said grille casing and said air supply duct, and means cooperating with said volume damper to define an inlet throat for admitting air from said duct to said grille casing, said inlet throat admitting air into said grille casing at a point spaced substantially from the point where said discharge means discharges air from said grille casing, whereby a plenum chamber of substantial volume is defined between said inlet throat and said discharge means so as to reduce the velocity and change the direction of flow of the air passing from said duct to said discharge means.

19. In air circulating apparatus for a room or the like, the combination of a relatively long grille casing extending substantially horizontally in said room and having a substantially horizontal slot therein for discharging air into said room in the form of a thin sheet of air distributed over a relatively wide area of the room, deflecting flange means extending lengthwise of said grille slot and adapted to be positioned to vertically deflect the air issuing from said grille slot, an air supply duct extending lengthwise along said grille casing for communication therewith along a substantial part of said grille casing, said air supply duct having air supplied thereto under pressure from a source of supply, and a relatively long volume damper movably mounted between said supply duct and said grille casing for controlling the volume of air transferred from said duct to said grille casing.

20. In air circulating apparatus for a room or the like, the combination of a relatively long grille casing extending substantially horizontally in said room and having a substantially horizontal grille slot therein for discharging air into said room in the form of a thin sheet of air distributed over a relatively wide area of the room, deflecting flange means extending substantially transversely of said grille slot and adapted to be positioned to laterally deflect the air issuing from said grille slot, an air supply duct extending lengthwise along said grille casing for communication therewith, said air supply duct having air supplied thereto under pressure from a source of supply, a volume regulating damper movably mounted between said supply duct and said grille casing,

and means for moving said damper to different positions.

21. In air circulating apparatus for a room or the like, the combination of a relatively long grille casing extending substantially horizontally in said room adjacent the ceiling thereof and having a substantially horizontal grille slot therein for discharging air into said, room near the ceiling in the form of a thin sheet of air distributed over a relatively wide area of the room, an air supply duct extending lengthwise along said grille casing for communication therewith along the major portion of the length of said grille casing, said air supply duct having air supplied thereto under pressure from a suitable source of supply, an inlet throat defined between said air supply duct and said grille casing, a controllable volume damper governing the size of said inlet throat, a thermal exchange conduit in said grille casing adjacent to said inlet throat whereby air passing through said throat into said grille casing impinges against said thermal exchange conduit, and means for moving said volume control damper.

22. In a duct system of air circulation for a room or the like, the combination of a supply duct extending substantially horizontally of said room in an overhead position, said duct adapted to receive air under pressure from a source of supply, a relatively long narrow grille casing extending substantially horizontally in said room in an overhead position lengthwise along said supply duct, a substantially horizontal plenum chamber defined between said supply duct and said grille casing, a relatively long restricted throat establishing communication from said supply duct to said plenum chamber, said plenum chamber and said restricted throat cooperating to reduce the velocity and change the direction of flow of the air passing from said supply duct into said plenum chamber, and relatively long substantially horizontal discharge means in said grille casing for discharging the air from said plenum chamber into the room at an overhead level in the form of a thin sheet of air distributed over a relatively wide area of the room.

7 JOHN R. BOYLE. 

